1. Field of the Invention
The present invention relates generally to hybrid vehicles, and, more particularly, to an energy storage apparatus for a hybrid motor vehicle.
2. Description of the Related Art
Since the invention of powered vehicles, many different powertrain systems have been attempted, including a steam engine with a boiler or an electric motor with a storage battery. It was, however, the four-stroke internal combustion engine invented by Otto in 1876, and the discovery of petroleum in 1859 that provided the impetus for the modern automotive industry.
Although gasoline emerged as the fuel of choice for automotive vehicles, recent concerns regarding fuel availability and increasingly stringent Federal and State emission regulations have renewed interest in alternative fuel powered vehicles. For example, alternative fuel vehicles may be powered by methanol, ethanol, natural gas, electricity or a combination of fuels.
A dedicated electric powered vehicle offers several advantages: electricity is readily available; an electric power distribution system is already in place; and an electric powered vehicle produces virtually zero emissions. There are several technological disadvantages that must be overcome before electric powered vehicles gain acceptance in the marketplace. For instance, the range of an electric powered vehicle is limited to approximately 100 miles, compared to about 300 miles for a gasoline powered vehicle. Further, the top speed is about half that of a similar gasoline powered vehicle. Significant advances in battery technology are required to overcome these technological disadvantages.
A hybrid powered vehicle, powered by electric and a gaseous fuel, overcomes the technical disadvantages of a dedicated electric vehicle while having almost the same environmental benefit as a dedicated electric vehicle. The performance and range characteristics are comparable to a conventional gasoline powered vehicle.
Therefore, there is a need in the art for a hybrid powertrain system in an automotive vehicle that is energy efficient, has low emissions, and offers the performance of a conventional gasoline powered vehicle.